<!DOCTYPE html>
<html>
<head>
    <title>File Upload Demo</title>
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link rel="stylesheet" href="/stylesheets/bootstrap.min.css"/>
</head>
<body>
<div class="container">
    <h1 class="text-center">扫描二维码上传文件</h1>
    <img class="center-block" src="/qr">
</div>
</body>
</html>